1. Field of the Invention
The invention relates to an apparatus for automatically forming a pointed end of a raw metal pipe such as aluminum pipe or the like which is subjected to drawing process, the pointed end being an extremity of said pipe and of such a reduced diameter as convenient for the drawing process.
2. Description of Prior Art
In the drawing process carried out for instance by the drawbench, an extremity of raw pipe is to be previously formed into a pointed end of reduced diameter so that the pointed end can be set through a drawing die and gripped by a chuck. The chuck is equipped in a drawing carriage disposed in front of the drawing die.
In general, a swaging machine is used to form such a pointed end. The drawing process has been employed also to manufacture base cylinders each supporting a photoconductive layer of such a photosensitive drum as incorporated in the electronic copiers, laser printers and the likes. The base cylinders must be of a high quality surface because they precisely support the photoconductive layers which are formed of selenium or organic photosensitive substances. According to a known operation in the process shown in FIG. 10, an operator 73 holds a middle or rear portion of a raw pipe 72 with special gloves on his hands. He inserts a front extremity of the pipe into a pipe inlet 74 of a swaging machine 71 so as to produce a pointed end at said extremity.
This manual operation for producing the pointed end however causes mental pressure and physical load to the operator, and such an operation is low in efficiency and productivity.
Further, the operator has to rely only on his keen scent to assure alignment of the pipe 72 with the swaging machine 71 during the operation. This has made it difficult for him to enhance an ideally linear shape to the pointed end, even with his excellent skillness. Directions in which said pointed ends deflect relative to the pipes are not constant, so that precision of the drawn pipes manufactured by means of the drawbench is affected. Yield of the products which can pass inspection is thus lowered.
Besides, there has been in the manual manufacture of the pointed ends a fear that peripheral surfaces of the raw pipes 72 would be scratched due to vibration of pipes during the swaging process, or be stained with small foreign particles even if a well skilled operator would work with his greatest carefulness and with the special gloves on his hands.